Process for making paper



March 22 1927.

L. KIRSCHBRAUN PROCESS FOR MAKING PAPER Filed March 27, 1924 Patented Mar. 22,1927

UNITED STATES PATENT oFri-ca.

misrnn .xmscnnaaun, or cnrcheo, rumors.

r toonss FOR name PAPER.

Application filed latch 21, 1924. Serial No. 102,316.

V This invention relates to improvements in process of making paper and refers more particularly to a proces' in which a greaseproofing layer is interposed between the in-' termediate plies of thesheet. One of the further objects of the invention is to make a waterproof or moistureproof'sheet containing a grease repellent layer between the plies and not exposed on the exterior surfaces of the sheet. The advantages of the invention will be apparent frbm the follow in% description in whichig. 1 is a somewhat diagrammatic view, partly in side elevation and (partly in vertical section, of cylinderrmol and application boxes, constitut ng part of the appa- ,ratus for carrying out'my -process.

Fig. 2 is an enlarged view of one of the application boxes, and associated feeding 11 leading from t 0 head box 12. The I tbs inner layer of which may be of, say 14 means.

Referrin to the draw 1 designates the vats mill 2 the cylinde nolds. In this instance, I have shown the cylinder molds spaced apart to accommodate the application boxes 3, hereinafter more particularly described. 4 designates the couch rolls, 5 the drum roll and 6 the blankets. 7 desig-- nates the adjustable contact rolls,"there being one for each of the application rolls 8.

Describing the application boxes and rolls, and referring more particularly to Fig. 2, each box 3 may be provided with a dam 9, feed line 10, havin suitable ,control valve proo "material previousl prepared s fed-into" t e head box throng the 1 13 from the sto tank 14 by means 02th; feedi pump 15. e overflow on the box 3 is drawn out throu h the outlet pipe 16 and suitable valve 17. pipe 16 is connected by suitable swingjoint 18 to swinging pipfi 19 which deliver to the funnel 20 throng which flmnel 20 the excess-in the head box is returned to the storage tank 14. The object of the swing jointis to maintain any desired level of the greaseproof material in the application box. By providinga number of application boxes, any of themcan be used for waterproofing while others are used for grease roofing, and still others are" being cleaned without stopping the operation.

The a plication ro ty of layers of smtable wire mesh,

mesh-and the outer layer so. mesh. The application rolls are suita ly rotated and may be covered with .the arrangement is such that the greaseproofing material may be continuously. applied to the under face of any ply. As the upper plies pass by the application rolls and are suitably coated, as stated, they meet the remainder of the plies formed on the cylinder-molds, and the result is that all of the plies are forced together to form a single sheet between which is interposed a layer or layers of greaseproof material. The sheet may then pass over the usual driers, where moisture is removed. From sheets, it is to be understood that it may be interposed between say, the second and third plies of a' fi-plysheet, or between the third and fourth plies of say, an 8-ply sheet; also, it may be interposed between both the third and fourth. and fifthand sixth plies of, say an 8-ply sheet by suitabl positioning the application rolls between t e cylinder molds. t is not necessary to mix the greaseproof material with the fibrous stock in the vat before the sheet is formed, but, nevertheless,

'asuitable greaseproo'flayer is formed between the plies, as the paper is being made.

The greaseproofing material ma be paraflin orglue, casein sulphite liquor, or leather dimlved in alkali, or analogous substances sus nded therein.

e process is particularly adapted to the making of containerboard or box board for packaging. greasy materials such asbutter,

meats and the like. Butter grease would dissolve and soak through ordinary water proof materials such as asphalt and like materials, and discolor the box blank.

I claim as m invention: 1. Process 0 making a grease-repellant multipl sheet comprising feltin separatel plies o' fibrous stock on the cylinder mold;

of a paper machine, interposing between certain of the wet pliw separatelayers of all rendered insoluble in water but and in subsequentlymniting the fibrous plies ,and greaseproof layers into a multiply sheet.

2.- A process of making a grease-repellant multiply sheet, comprising felting separately plies of fibrous stock on the cylinder molds.

of a paper machine, interposing between certain-of the wet plies a layer contact 'the surface of a rotating element carrying said grease-proofing material, and in subsequently uniting the fibrous plies and grease-proof layers into a multiply sheet.

3. A process v of making a grease and of grease- :repellant material by causingsaidplies to water-repellant multiply sheet comprising felting'sparatel'y plies of fibrous stock on cylinder molds of a paper machine,- interposing. between certain of the wet fibrous pliei a layer of grease-repellant material by PP repe lant material in the formed film, and also interposing between certain of the wet fibrous plies a layer of aterproofin material by applying 5 the same in the Wet fibrous plies, the fibrous plies, repellant layers into a multiply sheet.

LESTER KIRSCHBRAUN.

ing tothe wet fibrous plies said grease form of a pro-- f orm of a preformed film to the and subsequently uniting grease-repellant and water-- 

